The new Grand Prix in Baku, Azerbaijan threw up many surprises on arrival – the layout, the degree to which it favoured cars with greater engine power – but there were fewer surprises by the time the race came around.
As a high-speed street track, the indications from the support races were that this would be a race punctuated by Safety Cars, which would have a significant bearing on race strategy. But in the end it was a clean race and a relatively straight-forward one.
The most notable feature was Ferrari. One week after they took a gamble that failed in Canada, Ferrari seemed to be looking to do something different again on strategy. This time, instead of following orders, there was leadership from the cockpit of Sebastian Vettel’s car, which took the strategy in a different direction, while once again it didn’t work out particularly well for Kimi Raikkonen.
Free Practice had shown that a simple one stop strategy with around 20 laps on Supersofts and around 30 on softs should be the best way. But the Supersoft is a tricky race tyre, as we saw in Canada, where most teams avoided it on race day.
The temperatures rose on Sunday in Baku and that pushed some teams over the edge on tyre management. Red Bull, having committed to running low downforce levels to maintain a competitive top speed on the long straight, found that the car was sliding in the corners and this led to graining on the Supersoft and forced them to make much earlier stops than were ideal. They were constrained to running a two stop plan, which meant that Daniel Ricciardo went from the front row to seventh, one of only a handful of cars to use the Medium tyre. The Medium was relatively strong at the end of the race for Max Verstappen, but just not a fast enough tyre to be competitive.
Lewis Hamilton, starting tenth after a messy qualifying session, was obliged to follow a certain path in the race, due to a tyre set limitation for Supersoft tyres after his qualifying incidents led to a replacement tyre being issued. He was obliged to stick to Soft tyres for the race, after the first stint on Supersoft.
Most cars started on the Supersoft, but there were three drivers trying a ‘contra strategy’; a one stop starting with the Soft and a long first stint. These were Nico Hulkenberg, Marcus Ericsson and Pascal Wehrlein. It didn’t really work out for them, Hulkenberg only made it to Lap 20, and then left himself with 31 laps to do on the Supersoft, which meant he ran out of tyre performance at the end, always a big risk with that kind of strategy. Wehrlein made it to Lap 29 but then fitted the Mediums.
One stop or two?
The first proper pitstops were for Verstappen and Fernando Alonso: both came in extremely early on Lap five for Soft tyres. This committed them to a two stop.
Also suffering graining in his Red Bull, Ricciardo pitted on Lap six, having been overtaken by Vettel. Ferrari saw the threat of an undercut and called Vettel in. But unlike Canada he questioned the call, arguing that the car felt good on the tyres. It was not clear who made the final call, but this interaction via radio showed a maturing of the process between team and driver.
That said, the Ferrari strategy in Canada was deliberately done to do something different from the leading Mercedes, based on reasoning that they would not beat them by doing the same thing.
In Baku there was a realisation that Mercedes was just too strong in any condition and Vettel could see that the Red Bulls were struggling with tyre wear, so Vettel’s race wasn’t really with Ricciardo it was about filling the gap behind Rosberg and trying to retain it against the expected move up through the field by Hamilton. Fortunately for Vettel and Ferrari, Hamilton had power unit issues, which prevented him from reaching the four times world champion.
Although Vettel did not pit early, Raikkonen did come in as Ferrari split the strategies. This had the effect that when Vettel stopped he had been undercut by his team mate, who then let him through as he was on fresher tyres.
For the leading cars, in contrast to Red Bull, the tyre degradation on the Supersoft was actually quite low; after 16 Laps Rosberg was still going quicker lap-by-lap.
Mercedes was able to look after the tyres in low speed corners, high tyre pressures don’t affect, good mechanical grip and low speed traction, and combined with power of the Merc engine, on this track that favoured engine power
Hamilton stopped on Lap 15, so comparing him to Rosberg on Lap 17 (still on supersoft) – 1’49.1 vs Hamilton’s 1’48.1on Soft – we get 0.05-0.08s/lap degradation, which is on the low side and in line with increasing pace lap-by-lap as the fuel burns off. This equates to a degradation equal to the fuel effect of around 0.07s or lower.
Mercedes was easily the fastest team during the weekend and Rosberg just kept responding to Vettel’s pace after building a sizeable gap. After 15 or so laps he had enough gap that an Safety Car or Virtual Safety Car at the right moment could have enabled him to pit and still emerge ahead of Vettel and so the win would never have been in doubt.
This means that those stopping early on a two stop, or a one, for example Raikkonen, only have an advantage on covering the Safety Car for a very short time.
Everyone found the tyres were graining in the high track temperatures, but the answer was not to panic. Sergio Perez and Vettel saw this and extended their first stints, past the graining phase, to deliver strong podium results for their teams.
A final point worth noting is that, whereas the predictions for the brakes were that wear would be average, in fact there were more issues with brakes, simply because of the very high speeds and big stops.
The UBS Race Strategy Report is written by James Allen with input and data from several F1 team strategists and from Pirelli.
Race History Chart
Kindly provided by Williams Martini Racing, click to enlarge
Note the significant pace difference between the Mercedes and the rest, including Ferrari. Also look at the ‘undercut’ by Raikkonen (dotted red line) on Vettel (solid red line)